The invention relates to an odor removal system and more particularly to an odor removal system for toilet bowls.
The prior art includes a multitude of methods for removing odors from toilet bowls. A common approach can be seen in U.S. Pat. No. 6,550,072 to Ware in 2003. This approach includes an air intake at the toilet bowl, which is ducted to an exhaust fan installed away from the toilet. Another example of this approach can be found in U.S. Pat. No. 1,122,264 to Douglas in 1914. Although this approach is effective in removing odors, it has not received wide-spread commercial acceptance in 90 years. This could be due to the draw-backs of using an external fan. To install the fan in the room adjacent to the toilet is unsightly. Building the fan into the wall behind the toilet is problematic due to the plumbing pipes typically found in this location. Mounting the fan remotely in an attic or on the roof makes service more difficult and the installation more expensive.
Another approach is typified by U.S. Pat. No. 4,103,370 by Arnold. In this approach, the fan is located inside the toilet tank, and the air is exhausted to the sewer line. Although this approach is aesthetically pleasing it has disadvantages. This approach involves a redesign of the entire toilet. To install this toilet ventilation system would require the replacement of the entire toilet. Also there is a code problem with connecting the exhaust to the sewer line. Commonly, plumbing codes do not allow a connection to a sewer line unless protected by a water trap. It is not feasible to add a water trap to the exhaust duct in this concept.
U.S. Pat. No. 4,344,194 by Pearson and U.S. Pat. No. 4,853,981 by Hunnicutt have found the ideal location for the fanxe2x80x94in the toilet lid. To install a toilet ventilation system without replacing the entire toilet generally means that the toilet seat assembly be replaced. The toilet seat assembly typically incorporates the intake means, as well as the switching means. With the fan than in the seat assembly, the fan is installed when the seat assembly is replaced. The fan is readily accessible for service in this location.
If one considers the characteristics of the ideal toilet exhaust fan, the advantages of the lid location become more apparent. The ideal fan for toilet bowl ventilation produces relatively low airflow volume at relatively high pressure. Approximately 10 cubic feet per minute (cfm) of air volume is needed at 0.3 inch water column of pressure. A centrifugal blower is needed to achieve these flow characteristics at low noise levels. For centrifugal blowers, the diameter of the blower wheel contributes to pressure, and the width that contributes to volume. Thus the ideal blower wheel is relatively large in diameter, but small in width. A fan wheel of such proportions is well suited to fit inside the toilet lid when the wheel is oriented in the same plane as the lid.
U.S. Pat. No. 4,344,194 by Pearson and U.S. Pat. No. 4,853,981 by Hunnicutt have charcoal filters built into the lid in addition to the fans. Charcoal filters are intended to remove the odor so the air can be discharged back into the room, thereby avoiding ducting the exhaust to the exterior. Although this approach simplifies installation and improves aesthetics, it is less successful in achieving the basic goal of the ventilation systemxe2x80x94to remove the odors. Charcoal filters of the size that will fit in a toilet lid are less than 100% efficient at removing odors. Since the human nose is very sensitive to the odors in question the perceived performance of the charcoal filter approach is disappointing.
It is an object of the present invention to disclose an alternative venting toilet seat in which the fan is included in the toilet seat lid and connected to exhaust ducts. The air collected from the toilet bowl is driven by the fan into ducts which transport the collected air to a location remote from the toilet.
The present invention is a device for the removal of toilet bowl odors including a toilet seat lid having interior space. A fan is contained within the interior space and is in communication with an intake duct in the lid. When the lid is raised, the intake duct joins with an air passage formed by the mounting blocks to create a continuous air passage from the toilet bowl to the fan. This allows the fan to draw air from the toilet bowl. The fan discharges the air into one or more outflow ducts which extend from the side of the toilet lid. The device also includes a fan activation switch which is actuated by raising the toilet seat lid when the seat is down.
The outflow ducts may extend through a building wall and vent the air to outside a building. The outflow ducts may also be connected to an odor neutralization device located in the proximity of the toilet such as a charcoal filter system. The ducts may also be linked into a network of outflow ducts in a commercial building or other establishment having multiple toilets in close proximity.